This disclosure relates to refractory metal cores (RMC's). More particularly, this disclosure is directed to RMC finishing methodologies for providing an RMC having tailored properties for manufacturing a gas turbine engine part that is substantially free from defects.
Gas turbine engines typically include a compressor section, a combustor section, and a turbine section. During operation, air is pressurized in the compressor section and is mixed with fuel and burned in the combustor section to generate hot combustion gases. The hot combustion gases are communicated through the turbine section, which extracts energy from the hot combustion gases to power the compressor section and other loads.
Both the compressor and turbine sections may include alternating rows of rotating blades and stationary vanes that extend into the core flow path of the engine. Due to exposure to hot combustion gases, these components often include cooling circuits that receive and circulate cooling airflow for cooling the component. Some cooling circuits utilize microcircuits that are disposed inside the component to create a dual wall configuration.
Microcircuits and other cooling circuit technologies are commonly created using a RMC in conjunction with a ceramic core. Sharp edge breaks and the surface finish (i.e., rough, smooth, etc.) of the RMC are factors that can influence the quality of the component ultimately cast using the RMC.